Vertebrate Evolution is characterized by major locomotor adaptations that depend on the developmental potential of the somatic component of the lateral plate mesoderm (LPM). The paired appendages are perhaps the most dramatic of these morphological novelties, but innovations involving the LPM also include the sternum, gastralia, the turtle plastron, epi-pubis, the mammalian diaphragm, and many other muscular specialization of the lateral and ventral body wall of vertebrates. The obvious significance of LPM derived structures to the diversity of vertebrate locomotor and physiological strategies indicates that this embryonic cell population has played a major role in generating adaptive variation. This embryonic cell population, however, has rarely been the specific focus of evolutionary morphologists or developmental biologists. Given new EvoDevo models, growing data from non-model species, and discovery of tissue specific gene expression, it is an excellent time to consolidate data and questions regarding the lateral plate mesoderm. The organizers are seeking funding to offset the costs of registration and accommodations for the invited speakers participating in a symposium entitled "Evolution and Development in the Lateral Plate Mesoderm". This symposium will be part of the program of the Ninth International Congress of Vertebrate Morphology (ICVM 9) that will take place July 26-31 2010 in Punta del Esta, Uruguay. The symposium will bring together paleontologists, developmental, and evolutionary biologists, using both morphological and molecular approaches to discuss major morphological innovations occurring in the lateral plate mesoderm. PROJECT NARRATIVE: The lateral pate mesoderm provides essential cell populations and patterning information for major structures in the vertebrae musculoskeletal system. These structures are the site of major adaptive innovations in vertebrate lineages, as well as devastating birth defects in humans. Most birth defects in the human musculoskeletal system result from miss patterning of embryonic cell populations. The remarkable knowledge we have concerning these processes derives directly from study of nonhuman vertebrates. A clear knowledge of specific developmental systems is essential to successfully applying new technologies to the treatment and eventual prevention of birth defects.